We propose to build a device to quantify new simplified semen assays. Novel colorimetric assays for semen evaluation have recently been validated in independent clinical studies and will be introduced commercially in 1997. These MARQ (male reproductive quality) assays operate by filtering, staining and visually examining sperm cells. These assays comprise rapid, inexpensive diagnostic kits for a physician's office, to screen those patients who should be referred to a fertility specialist. They provide simple, semi-quantitative analysis of selected semen parameters including sperm concentration, sperm viability, and leukocyte count. Semen analysis by microscope is CLIA-classified as highly complex, and is subject to significant observer error. Therefore an improved measure of sperm concentration and other parameters is needed if patient screening is to be permissible in the physician's office. We propose to develop a prototype semen-evaluation colorimeter for application both to low- and to high-volume settings. The Prototype is designed to quantitate the color endpointproduced by the MARQ assays. It combines recently-developed optical sources, microcomputer control, CPU-controlled strobed light sources and detectors together with rapid analog/digital conversion to give an accurate, compact, simple and inexpensive instrument. The Prototype reader will be designed, built, tested and validate. PROPOSED COMMERCIAL APPLICATION: The Prototype and assays will be used by general practitioners, OBGYNs, urologists, and fertility clinics. More than 11 million semen analyses are performed annually world wide for infertility screening, quality control in sperm banks, male contraceptive research and post-vasectomy follow-up. The low price and the anticipated accuracy indicates a potential market of more than 100,000 sites. The accuracy, low cost and ease-of-use of the proposed MARQ Reader should prove particularly important in the managed care medical environment as well as in less developed countries.